Drill pipe valve



April 28, 1959 J. o. MELTON ET AL 2,884,002

DRILL PIPE VALVE Filed Oct. 14. 1957 2 Sheets-Sheet 2' v l6 INVENTORSJames 0. Me/fon lr w'n M Unrpenfer ATTORNEYS United States Patent DRILLPIPE VALVE James 0. Melton, Norman, and Irvin M. Carpenter, OklahomaCity, Okla, assignors to The Geolograph Conn pany, Oklahoma City, Okla.,a partnership Application October 14, 1957, Serial No. 690,066

.6 Claims. (Cl. 137454.2)

The present invention relates to well-drilling equipment and moreparticularly to a valve, generally referred to as a back pressure valve,which will permit the automatic filling of a drill string with drillingfluid as the string is lowered into the well bore.

In the drilling of bore holes through earth formations in the ground, itis conventional practice to force drilling fluid downwardly through thecenter of the drill string, then upwardly around the outside of thedrill string, and back to the pumping means at the surface. It is alsoconventional to employ a back pressure valve at the lower end of thedrill string to prevent any liquid from flowing in the reverse directionfrom the well bore into the drill string. in this fashion the drillingliquid (or mud) can flow in but one direction.

However, since the drill string must be removed from the well bore fromtime to time for the purpose of changing the drill bit, or for othervarious reasons, it becomes necessary to provide means for temporarilydisabling the back pressure valve prior to the reintroduction of thedrill string into the well bore; otherwise, of course, if the drillstring were lowered into the well bore with the back pressure valveoperating in its conventional manner, this valve would effectivelyprevent any liquid from entering the drill string, such that, when thenow empty drill string reached a certain depth below the surface of theground, the pressure of the fluid in the well bore would cause the drillstring to collapse.

The operators and engineers in the field have long recognized theproblem stated above and, as a result, several back pressure valves havebeen designed with means for temporarily disabling them prior to thereintroduction of the drill string into the well bore. In most instancesthe disabling means referred to above consists of a frangible elementwhich locks the back pressure valve in an open position and retains itin such a position until the drill string has been lowered to thedesired depth. At this point, the drilling mud is forced into theinterior of the drill string exerting a pressure against the frangibleelement so as to break the same and thus cause the back pressure valveto return to its normal or conventional mode of operation.

The first and most obvious disadvantage of the above type of valve isthat the frangible means has to be replaced each and every time that thedrill string is removed from the well bore.

Therefore, a principal object of the present invention is to provide animproved back pressure valve of the type referred to above wherein thetemporary disabling means forms a permanent part of the valve unit andwherein said disabling means may be simply manipulated to disable thesaid valve temporarily, and wherein said disabling means may bethereafter simply disengaged to return the valve to its normalfunctioning operation,

Another object of the present invention is to provide an automatic backpressure valve of the, type referred to above, including the disablingmeans, wherein said valve ice is of simple yet rugged construction andwhich is relatively economical to manufacture.

Other and further objects and advantageous features of the presentinvention will hereinafter more fully appear from a detailed descriptionof the drawings in which Figure 1 is an elevational view showing theexterior of the enclosed valve;

Figure 2 is a longitudinal section view taken along line 2-2 of Figure 1showing the valve in its disabled condition;

Figure 3 is a transverse sectional view taken along section line 33 ofFigure 2 showing the relationship between the valve stem (or rod) andthe disabling means;

Figure 4 is a section view similar to Figure 2 showing the valve in itsnormal operating condition with the disabling means disengaged;

Figure 5 is a transverse sectional view taken along section line 5--5 ofFigure 2 showing the relationship between the valve interior and thedisabling means when the valve is disabled;

Figure 6 is a longitudinal and fragmentary section view taken along line66 of Figure 4 showing the relationship between the valve stem anddisabling means when the valve is in its normal operating condition;

Figure 7 is a fragmentary sectional view taken along the line 7--7 ofFigure 4 showing the relationship between one end of the cross bar andits seat in the side of the valve casing;

Figure 8 is a perspective view on an enlarged scale of the disablingmeans of the present invention.

Referring to the drawings in detail, reference numeral 10 designates theouter casing of the valve which is received and supported in a lowersection of the drill string immediately above the portion thereofsupporting the drill bit. Any convenient means for attaching, securing,or receiving said valve casing within a section of said drill string(not shown) may be employed. However, purely for purposes ofillustration, there are shown at the top of the valve casing 10 threeslits 11, etc. which will fit into corresponding projecting portions ofor in the drill string section in which the valve is to be located.Also, there are shown two annular grooves 12, 12 and interfittingO-rings 13, 13 which provide a convenient seal against the inside of theassociated drill string section.

Valve casing 10 has a lower section 14 which is threaded thereto as at15. On the inside of the lower casing section 14 immediately below thejuncture between this element and the main section 10 thereof there areprovided a pair of diametrically opposed bosses 16, 16 (see also Figure7) having oppositely aligned rectangular depressions 17 for receivingtherein the opposite ends of a cross bar 18. Cross bar 18 has acentrally located hole '19 which serves to locate the lower end of a rodor valve stem 26 which is freely reciprocable through this hole. Abullet-shaped valve head 21 is attached to the upper end of the valvestem 20. At the upper end of the valve casing 10 there is provided aninternal bore 22 of reduced diameter relative to the diameter of themain bore 23. The curved surface interconnecting bores 22 and 23 forms aseat 24 for the valve head 21.

Seated on the upper surface of the cross bar 18 is a collar 25 having ahole 26 for permitting passage therethrough of the valve stem 20. Asbest shown in the Figures 4 and 6, the cross bar 18 is provided with anupwardly projecting portion 28 which fits into a correspondingly shapedrecess 29in the collar 25. A helical spring 27 surrounding the valvestem 20 bears against the lower surface of the valve head 21 andtheupper surface of the collar 25 so as to resiliently urge the valve head21 in an upward direction towards the .valve seat :24. Adjacent themid-portion of the cross bar 18 and projecting downwardly therefrom onopposite sides of the aee aooz valve stem 20, are a pair of arms 30, 30having integral and outwardly projecting pins 31, 31.

Referring now especially to Figure 8, the valve disabling'means of thepresent invention constitutes a pivotal flapper 32 having a pair ofspaced parallel flat portions 33, 33 in which are located aligned holes34, 34. The latter are adapted to fit onto the projecting pins 31, 31.At one end of the flapper 32 extending at right angles to the flatportions 33, 33 is a substantially flat vane 35. At the opposite ends ofthe flat portions 33, 33 is a hollow and semi-cylindrical member 36which is secured to the members 33, 33 by the cross member 37. Thesemicylindrical member 36 which constitutes a latching means extends atsubstantially right angles to the plane of the vane 35. The insidehollow surface 33 of the semicylindrical member 36 is substantially ofthe same diameter as the valve stem 20 (see Figure 3). The lower end ofthe valve stem 20 is provided with an enlarged rounded portion 39 theupper surface of which can engage the outer edge of the semi-cylindricallatching means 36 as shown in Figure 2.

In order to prevent the flapper 32 from vibrating unnecessarily ineither of its two positions as represented by Figures 2 and 4,respectively, the collar 25 is provided with two downwardly projectingportions 40, 40 which extend on opposite sides of the cross bar 18 andterminate adjacent the flapper 32, as best shown in Figures 4 and 6. Theflapper itself (see Figure 8) has, on its fiat portions 33, 33 a pair ofstraight side edges 41, 41 which, in the Figure 4 position, will coactwith the downward projecting portions 40, 40 of the collar 25 to preventundue vibration of the flapper 32. These flat portions 33, 33 are alsoprovided with curved side edges 42, 42 adjacent the vane 35 whichportions will bear against lower edges of extending portions 40, 40, asshown in Figure 2, such that a part of the spring pressure exertedagainst the collar 25 will also be exerted against the flapper 32 tohold the same in the Figure 2 position.

The operation of the valve will now be briefly described as follows:Starting from the position shown in Figure 4 which represents the normaloperating condition of the valve, and assuming that the lowermostsection of the drill string has been raised to the surface, the lowerend 39 of the valve stem 20 may be pulled downwardly and the flapper 32pivoted counter clockwise until the inner surface 38 of thesemi-cylindrically shaped member 36 bears against the valve stem 20; atthis point, the valve stem 20 is released and the enlarged roundedportion 39 will, through the action of the spring 27, be forced upwardlyagainst the lower edge of the semicylindrical portion 36. In thisposition, the valve stem 20 will be firmly locked in place as shown inFigure 2. Thus, as the drill string is lowered into the ground, thedrilling fluid may pass upwardly on the opposite sides of cross bar 18through the space between the valve head 21 and the valve seat 24 andthence into the main body of the drill string. Although the vane 35 willbe occupying a portion of the free cross-sectional area on oppositesides of the cross bar 18, as shown in Figure 6, nevertheless, thereremains suflicient open space to permit the passage of the drillingfluid upwardly therethrough as the drill string is lowered into thehole.

When the drill string reaches its lowermost limit where the operatorwishes to return the valve to its normal operating condition, thedrilling mud is simply pumped downwardly in the drill string. Thedownward pressure of the flowing fluid will then be exerted against thevane 35 so as to pivot the flapper in a clockwise direction, thusreleasing the valve stem 20 from the restraint of the semi-cylindricallatching member 36 and returning the valve to the condition shown inFigure 4. The valve will now operate as a one-way, back pressure valve.

Whereas the instant invention has been described in particular relationto the drawings illustrated herein,

other and further modifications, apart from those shown i. or suggestedherein, may be made within the scope and spirit of this invention.

What is claimed is:

1. In a valve of the type described, a hollow valve casing, a valvehead, a valve stem supporting said valve head, means on the innersurface of said casing forming a seat for said valve head, means forresiliently urging said valve head toward said valve seat, a radiallyprojecting abutment on said valve stem, at pivotally mounted lockingmeans supported within said casing and having thereon a vane covering aportion of the free internal cross-sectional area of said valve casingwhen said locking means is in its locking position, said vane beingmovable away from its position covering said portion of said area whensaid locking means is pivoted away from its locking position, saidlocking means including a stemengaging means for engaging said abutmenton said valve stem and for holding said valve head away from said valveseat against the action of said resiliently urging means when saidlocking means is in its locking position, said stem-engaging means beingmovable out of engagement with said abutment when said locking means ispivoted away from its locking position.

2. In a valve of the type described including a hollow valve casing, avalve head, a valve stem supporting said valve head, means on the innersurface of said casing forming a seat for said valve head, and a springmeans for resiliently urging said valve head toward said valve seat, theimprovement which comprises an abutment on said valve stem, and apivotally mounted locking means supported within said casing and havingthereon a stemengaging means for engaging said abutment and holding saidvalve head away from said valve seat when said locking means is pivotedto its locking position, said stem-engaging means being movable out ofengagement with said abutment when said locking means is pivoted awayfrom its locking position, said locking means also including a vane forcovering a portion of the free internal cross-sectional area of saidvalve casing when said locking means is in its locking position, saidvane being movable away from its position covering said portion of saidarea when said locking means is pivoted away from its locking position,whereby, with said locking means in its locking position, as a stream offluid is forced through said valve in a direction from said valve headtowards said locking means and against said vane, said vane will beforced downwardly such that said locking means will pivot to move saidstem-engaging means out of contact with said abutment and said valve isreturned to its normal operating condition.

3. In a valve of the type described, a valve casing shaped in the formof a hollow upright cylinder, a valve head, a valve stem attached tosaid valve head and extending downwardly therefrom, a portion of theinner surface of said casing forming a seat for said valve head, springmeans for resiliently urging said valve head upwardly toward said valveseat, a projecting abutment on said valve stem adjacent the lower endthereof, a pivotally mounted flapper supported within said casingadjacent the lower end of said stem and having thereon a vane forcovering a portion of the free internal cross-sectional area of saidvalve casing when said flapper is pivoted to its locking position, saidvane being movable out of its position covering said portion of saidarea when said flapper is pivoted out of its locking position, saidflapper having a latching means for engaging said abutment and holdingsaid valve head away from said seat when said flapper is in its lockingposition, said latching means being movable out of engagement with saidabutment when said flapper is pivoted away from its locking position,whereby said valve stem may be urged downwardly and whereby said flappermay be pivoted simultaneously to engage said latching means with saidabutment, thereby locking said valve stem in position, and whereby, asa. stream of fluid is forced downwardly through said valve and againstsaid vane, said flapper may be pivoted such that said latching means isreleased from said abutment and said valve is returned to its normaloperating condition.

4. In a valve of the type described, a hollow valve casing, a valvehead, a valve stem supporting said valve head, means on the innersurface of said casing forming a seat for said valve head, a fixedsupport means secured to the inside of said valve casing and spaced fromsaid valve seat for slidably engaging said valve stem and for holdingthe same in axial alignment with said casing, means coacting betweensaid valve head and said support means for resiliently urging said valvehead toward said valve seat, a radially projecting abutment on saidvalve stem, and a locking means pivotally mounted intermediate its endson said support means and having on one end a vane for covering aportion of the free internal cross sectional area of said valve casingwhen said locking means is in its locking position, said vane beingmovable away from said position covering said portion of said area whensaid locking means is pivoted out of its locking position, said lockingmeans having at its other end a stem-engaging means for engaging saidabutment on said valve stem and for holding said valve head away fromsaid valve seat against the action of said resiliently urging means whensaid locking means is in its locking position, said stem-engaging meansbeing movable away from engagement with said abutment when said lockingmeans is pivoted away from its locking position.

5. In a valve of the type described including a hollow valve casing, avalve head, a valve stem supporting said valve head, means on the innersurface of said casing forming a seat for said valve head, a fixedsupport means secured to the inside of said valve casing and spaced fromsaid valve seat for slidably engaging said valve stem and for holdingthe same in axial alignment with said casing, and a spring meanscoacting between said valve head and said support means for resilientlyurging said valve head toward said valve seat, the improvement whichcomprises an abutment on said valve stem, and a locking means pivotallymounted on said support means and having thereon a stem-engaging meansfor engaging said abutment and holding said valve head away from saidvalve seat when said locking means is pivoted to its locking position,said stem-engaging means being movable out of engagement with saidabutment when said locking means is pivoted away from its lockingposition, said locking means also including a vane for covering aportion of the free internal cross-sectional area of said valve casingwhen said locking means is in its locking position, said vane beingmovable away from its position covering said portion of said area whensaid locking means is pivoted away from its locking position, whereby,with said locking means in its locking position, as a stream of fluid isforced through said valve in a direction from said valve head towardssaid locking means and against said vane, said vane will be forceddownwardly such that said lock ing means will pivot to move saidstem-engaging means out of contact with said abutment and said valve isreturned to its normal operating condition,

6. In a valve of the type described, a valve casing shaped in the formof a hollow upright cylinder, a valve head, a valve stem attached tosaid valve head and extending downwardly therefrom, a portion of theinner surface of said casing forming a seat for said valve head, across-bar attached to and extending across the interior of said casingbelow said valve seat, said cross-bar having a hole therein forpermitting sliding movement of said valve stem therethrough whilemaintaining said valve stem in axial alignment with the longitudinalaxis of said casing, spring means coacting between an upper portion ofsaid cross-bar and a lower portion of said valve head for resilientlyurging said valve head upwardly toward said valve seat, a projectingabutment on said valve stem adjacent the lower end thereof, a flapperpivotally mounted on said cross-bar adjacent the lower end of said stemand having thereon a vane for covering a portion of the free internalcross-sectional area of said valve casing when said flapper is pivotedto its locking position, said vane being movable away from its positioncovering said portion of said area when said flapper is pivoted awayfrom its locking position, said flapper having a latching means forengaging said abutment and holding said valve head away from said seatwhen said flapper is in its locking position, said latching means beingmovable out of engagement with said abutment when said flapper ispivoted away from its locking position, whereby said valve stem may beurged downwardly and whereby said flapper may be pivoted simultaneouslyto engage said latching means with said abutment, thereby locking saidvalve stem in position, and whereby, as a stream of fluid is forceddownwardly through said valve and against said vane, said vane will beforced downwardly such that said flapper will be pivoted such that saidlatching means is released from said abutment and said valve is returnedto its normal operating condition.

References Cited in the file of this patent UNITED STATES PATENTS

